XPath, the XML Path Language, is a query language for selecting nodes from an XML document. In addition, XPath may be used to compute values (e.g., strings, numbers, or Boolean values) from the content of an XML document. XPath was defined by the World Wide Web Consortium (W3C).

Dereference

In the examples we're making queries from repository root node, but really the queries might be done from /jcr:root/okm:root/ - that's the taxonomy node - for example the locked documents might be done as

/jcr:root/okm:root//element(*, okm:document)[@jcr:lockOwner]

Type restrictions

We can specify the type of node that query returns. Restrictions include inheritage all subtype are included as possible results. The function element is used to evaluate a node type.

For example the node folders

//element(*, okm:folder)

Property restrictions

A query can have property restrictions. The operators used are (=, !=, <, <=, >, >=) in addtion there's some extra operators like jcr:like() and jcr:contains().

Getting folders with author pito

//element(*, okm:folder)[@okm:author = 'pito']

Documents name starting with linux

//element(*, okm:document)[jcr:like(@okm:name, 'linux%')]

Documents with indexed content jackrabbit

//element(*, okm:resource)[jcr:contains(., 'jackrabbit')]/@jcr:path

Order

At ends query can be indicated the order of results.

Ordering by name

//element(*, okm:document)[@okm:keywords != ''] order by @okm:name

Usually is used jcr:score to ordering, that indicates de ranking of the results.